tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.19.y head: 030194a5b292bb7613407668d85af0b987bb9839 commit: 31ebc2fe02df202566d0e36c1106b4902d6e2f8c [2158/3560] powerpc/64s: flush L1D after user accesses config: powerpc64-randconfig-r025-20210311 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 574a9dabc63ba1e7a04c08d4bde2eacd61b44ce1) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install powerpc64 cross compiling tool for clang build # apt-get install binutils-powerpc64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.gi... git remote add linux-stable-rc https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git git fetch --no-tags linux-stable-rc linux-4.19.y git checkout 31ebc2fe02df202566d0e36c1106b4902d6e2f8c # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All error/warnings (new ones prefixed by >>): In file included from arch/powerpc/kernel/asm-offsets.c:16: In file included from include/linux/compat.h:12: In file included from include/linux/stat.h:19: In file included from include/linux/time.h:6: In file included from include/linux/seqlock.h:36: In file included from include/linux/spinlock.h:54: In file included from include/linux/irqflags.h:16: In file included from arch/powerpc/include/asm/irqflags.h:12: In file included from arch/powerpc/include/asm/hw_irq.h:64: In file included from arch/powerpc/include/asm/paca.h:21: In file included from arch/powerpc/include/asm/lppaca.h:36: In file included from arch/powerpc/include/asm/mmu.h:313: In file included from arch/powerpc/include/asm/book3s/64/mmu.h:30: In file included from arch/powerpc/include/asm/book3s/64/mmu-hash.h:24: arch/powerpc/include/asm/book3s/64/pgtable.h:1292:15: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers] static inline const int pud_pfn(pud_t pud) ^~~~~~ In file included from arch/powerpc/kernel/asm-offsets.c:16: In file included from include/linux/compat.h:19: In file included from include/linux/uaccess.h:14: In file included from arch/powerpc/include/asm/uaccess.h:9: In file included from arch/powerpc/include/asm/kup.h:10: DECLARE_STATIC_KEY_FALSE(uaccess_flush_key); ^ int DECLARE_STATIC_KEY_FALSE(uaccess_flush_key); ^ if (static_branch_unlikely(&uaccess_flush_key)) ^ if (static_branch_unlikely(&uaccess_flush_key)) ^ In file included from arch/powerpc/kernel/asm-offsets.c:23: include/linux/mman.h:133:9: warning: division by zero is undefined [-Wdivision-by-zero] _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/mman.h:111:21: note: expanded from macro '_calc_vm_trans' : ((x) & (bit1)) / ((bit1) / (bit2)))) ^ ~~~~~~~~~~~~~~~~~ include/linux/mman.h:134:9: warning: division by zero is undefined [-Wdivision-by-zero] _calc_vm_trans(flags, MAP_SYNC, VM_SYNC ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/mman.h:110:48: note: expanded from macro '_calc_vm_trans' ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \ ^ ~~~~~~ include/linux/mman.h:134:9: warning: division by zero is undefined [-Wdivision-by-zero] _calc_vm_trans(flags, MAP_SYNC, VM_SYNC ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/mman.h:111:21: note: expanded from macro '_calc_vm_trans' : ((x) & (bit1)) / ((bit1) / (bit2)))) ^ ~~~~~~~~~~~~~~~~~ 5 warnings and 3 errors generated. -- In file included from arch/powerpc/kernel/asm-offsets.c:16: In file included from include/linux/compat.h:12: In file included from include/linux/stat.h:19: In file included from include/linux/time.h:6: In file included from include/linux/seqlock.h:36: In file included from include/linux/spinlock.h:54: In file included from include/linux/irqflags.h:16: In file included from arch/powerpc/include/asm/irqflags.h:12: In file included from arch/powerpc/include/asm/hw_irq.h:64: In file included from arch/powerpc/include/asm/paca.h:21: In file included from arch/powerpc/include/asm/lppaca.h:36: In file included from arch/powerpc/include/asm/mmu.h:313: In file included from arch/powerpc/include/asm/book3s/64/mmu.h:30: In file included from arch/powerpc/include/asm/book3s/64/mmu-hash.h:24: arch/powerpc/include/asm/book3s/64/pgtable.h:1292:15: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers] static inline const int pud_pfn(pud_t pud) ^~~~~~ In file included from arch/powerpc/kernel/asm-offsets.c:16: In file included from include/linux/compat.h:19: In file included from include/linux/uaccess.h:14: In file included from arch/powerpc/include/asm/uaccess.h:9: In file included from arch/powerpc/include/asm/kup.h:10: DECLARE_STATIC_KEY_FALSE(uaccess_flush_key); ^ int DECLARE_STATIC_KEY_FALSE(uaccess_flush_key); ^ if (static_branch_unlikely(&uaccess_flush_key)) ^ if (static_branch_unlikely(&uaccess_flush_key)) ^ In file included from arch/powerpc/kernel/asm-offsets.c:23: include/linux/mman.h:133:9: warning: division by zero is undefined [-Wdivision-by-zero] _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/mman.h:111:21: note: expanded from macro '_calc_vm_trans' : ((x) & (bit1)) / ((bit1) / (bit2)))) ^ ~~~~~~~~~~~~~~~~~ include/linux/mman.h:134:9: warning: division by zero is undefined [-Wdivision-by-zero] _calc_vm_trans(flags, MAP_SYNC, VM_SYNC ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/mman.h:110:48: note: expanded from macro '_calc_vm_trans' ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \ ^ ~~~~~~ include/linux/mman.h:134:9: warning: division by zero is undefined [-Wdivision-by-zero] _calc_vm_trans(flags, MAP_SYNC, VM_SYNC ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/mman.h:111:21: note: expanded from macro '_calc_vm_trans' : ((x) & (bit1)) / ((bit1) / (bit2)))) ^ ~~~~~~~~~~~~~~~~~ 5 warnings and 3 errors generated. make[2]: *** [./Kbuild:56: arch/powerpc/kernel/asm-offsets.s] Error 1 make[2]: Target '__build' not remade because of errors. make[1]: *** [Makefile:1123: prepare0] Error 2 make[1]: Target 'prepare' not remade because of errors. make: *** [Makefile:146: sub-make] Error 2 make: Target 'prepare' not remade because of errors. vim +5 arch/powerpc/include/asm/book3s/64/kup-radix.h 4 6 7 /* Prototype for function defined in exceptions-64s.S */ 8 void do_uaccess_flush(void); 9 10 static __always_inline void allow_user_access(void __user *to, const void __user *from, 11 unsigned long size) 12 { 13 } 14 15 static inline void prevent_user_access(void __user *to, const void __user *from, 16 unsigned long size) 17 { 19 do_uaccess_flush(); 20 } 21 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org